Video production proceeds according to a script. Normally, video production includes shooting some video footage, editing the shot footage, and splicing stock video clips with the edited footage as necessary to prepare the final video product.
Generally, the production of video content involves assembling video from multiple sources. Consider, for example, producing a documentary about a ski resort. The documentary team may have captured some footage at the ski resort location. During post production, as the video is edited, it becomes evident that the script of the video requires footage beyond what was captured during the initial on-location shoot.
Supplemental video content, often from stock video, that is added into a video production is known as B-roll footage. Typically, the editing personnel view a collection of supplemental video clips and select those supplemental video clips that they deem suitable according to the script.
In some cases, metadata of a video clip provides some information about the lead actors or significant characters in the video clip, date of publication, a summary of the story of the video clip, licensing and ownership information, and other such information. When available, such metadata is useful in shortlisting some supplemental video clips from a sizeable collection of supplemental video content. The editing staff must then view each shortlisted video clip and select some, all, or none of the shortlisted video clip for use in the video according to the script.
In some cases, some videos are created entirely from stock footage. In such cases as well, during production, the editing staff has to view, select, and assemble that supplemental video clip which relates to the script for the video.